I have had multiple guns have their stats just change. At first I thought I was crazy when I was seeing this, and just sold the guns - as the damage was significantly reduced. Now I have found 2 very solid weapons and have been using them for a while, so I have a longer time frame where I have been able to see the stats flip on these guns multiple times. They always seem to flip from the drop stats to some second set of stats, and back again, I have witnessed it on more than a few occasions and it seems to happen upon login - but definitely not every login. I took some screenshots to show you what i mean.
Has anyone else experienced this? As you can see from the screenshots below, the drop version of the first gun has disturbingly good stats when compared to what it alters to. The quest legendary was worse on the drop than what it changes to. I assumed the weapons just got patched or something, but nothing is in the patch notes about any gun changes…and then they kept flipping between these two sets of stats.